Le_Forgeron <lef### [at] freefr> wrote:
> Well, you are going to have issue with the video industry.

> DVD NTSC: 720 x 480 (3:2) for 4:3 & 16:9, none of the pixel is square.
> DVD Pal : 720 x 576 (5:4) also for 4:3 & 16:9, not a square pixel in
> sight either.

> VCD & SVCD did neither use square pixel.

  Also, the major problem is: If you wanted POV-Ray to always assume square
pixels and then someone renders the image with a different aspect ratio
than what the camera is, what should POV-Ray do? There are quite many
possibilities:

  - Always extend or crop the image horizontally.
  - Always extend or crop the image vertically.
  - Only extend the image (either horizontally or vertically, depending on
whether the image aspect ratio is wider or narrower than the camera aspect
ratio).
  - Only crop the image (likewise).
  - Perform a combination of both.

  The problem with cropping the image is that important parts of the
scenery might get cropped away, destroying the original image composition.
Extending the image might be even worse, as unmodeled parts of the scenery
could become visible, severely degrading the quality of the end result.

  If POV-Ray supported automatic aspect ratio tuning, the *author* of the
image should have a saying in it, rather than the decision being solely
on the person who renders the image (who might not be the same person).

  I discuss with these issues in more detail and have a suggestion here:
http://bugs.povray.org/task/85

-- 
                                                          - Warp

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